Agility Robotics / Oregon State University (USA) Cassie (1)

Agility Robotics / Oregon State University (USA) Cassie (2)

Was ~$250,000 – $300,000Sold to research labs from 2017. Reported prices range from about $250,000 to $300,000 per unit, and Agility built only a small batch (just over a dozen, unconfirmed). Agility later retired Cassie in favor of Digit.

Discontinued · unavailableRL walkingLegs onlySeries-elastic legsGuinness 100 m recordSim-to-real RL

UnavailableShipping: Not available. Retired by Agility Robotics. Only a small number of research units exist, mostly in university labs.

IEEE Spectrum launch article ↗OSU Guinness record ↗ROBOTS guide ↗

Overview

An ostrich-inspired pair of legs with no upper body, introduced in February 2017 by Oregon State spinout Agility Robotics as the successor to OSU's ATRIAS. Research groups at OSU, Michigan and Berkeley used it for landmark learned-locomotion work, including an untethered 5 km run in 2021 and a Guinness record 100 m sprint in 2022. Its leg design carried into Agility's humanoid Digit, which replaced it.

Specifications

Category	Bipeds · Research & legacy bipeds
Released	2017
Country	USA
Availability	Discontinued · unavailable
Programmability	Full SDK
Best for	Professionals & labs
Vision sensors	No vision sensors
Actuators	Brushless / direct-drive motors
Audio	No audio
Compute type	x86 PC (Intel / AMD)
Balance type	RL walking
Height	115 cm
Weight	31 kg
Compute	Intel Atom real-time control computer plus an Intel NUC (i5) secondary computer
Speed	About 4 m/s top speed, 100 m in 24.73 s (Guinness record, 2022)
DOF	10 actuated (5 per leg), plus passive spring joints in shin and ankle
Sensors	IMU, absolute and incremental joint encoders. No cameras or lidar as standard.
Balance	Underactuated dynamic walking and running with compliant legs. Research labs used model-based control and sim-to-real reinforcement learning policies.
SDK	MATLAB Simulink Real-Time on the control computer, any software on the secondary PC. Open simulation models and community tools (e.g. cassie-mujoco-sim)